The present invention relates to electronics assemblies, and is primarily concerned with racked assemblies. Many such assemblies will be located in racks for housing in for example nineteen inch cabinets, or other size cabinets such as twenty three inch cabinets or metric cabinets. The assemblies may for instance be employed as servers for a number of systems, for example in local area networks (LANs), wide area networks (WANs), telecommunications systems or other operations such as database management or as internet servers.
Such an assembly will typically comprise a supporting chassis or frame that houses a motherboard or backplane and a number of daughterboards or module cards that extend in planes generally perpendicular to the plane of the motherboard. One form of assembly includes so-called “RAS computers” that is to say, computers that need to provide a high degree of reliability, availability and serviceability, and which therefore need to maximise the length of time during which the computer is operational.
Where any parts of the computer need to be replaced, it is advantageous if they can be replaced without needing to switch the computer off. The serviceability, including typical time to replace parts and special tool requirements can also contribute to the system availability by affecting the probability of repair success.